Prepare your pie dough by mixing and forming it into a disc, then refrigerate overnight.

In a medium saucepan, combine the sour cherries, sugar, lemon juice, and cornstarch. Cook until thickened.

Roll out the chilled pie dough to about 1/8 inch thick and cut into 4-inch rounds.

Spoon about 1/4 cup of filling onto one dough circle, cover with another circle, and seal by crimping edges.

Freeze assembled pies for 30 minutes if not baking immediately.

Preheat oven to 400°F, brush tops with egg wash, and bake for 30-40 minutes until golden brown.